diff --git a/src/interfaces/libpq/fe-exec.c b/src/interfaces/libpq/fe-exec.c
index 832d61c544f..7bd5b3a7b9d 100644
--- a/src/interfaces/libpq/fe-exec.c
+++ b/src/interfaces/libpq/fe-exec.c
@@ -1329,7 +1329,8 @@ PQsendQueryInternal(PGconn *conn, const char *query, bool newQuery)
 	{
 		/*
 		 * In pipeline mode we cannot use the simple protocol, so we send
-		 * Parse, Bind, Describe Portal, Execute.
+		 * Parse, Bind, Describe Portal, Execute, Close Portal (with the
+		 * unnamed portal).
 		 */
 		if (pqPutMsgStart('P', conn) < 0 ||
 			pqPuts("", conn) < 0 ||
@@ -1355,6 +1356,11 @@ PQsendQueryInternal(PGconn *conn, const char *query, bool newQuery)
 			pqPutInt(0, 4, conn) < 0 ||
 			pqPutMsgEnd(conn) < 0)
 			goto sendFailed;
+		if (pqPutMsgStart('C', conn) < 0 ||
+			pqPutc('P', conn) < 0 ||
+			pqPuts("", conn) < 0 ||
+			pqPutMsgEnd(conn) < 0)
+			goto sendFailed;
 
 		entry->queryclass = PGQUERY_EXTENDED;
 		entry->query = strdup(query);
diff --git a/src/test/modules/libpq_pipeline/traces/pipeline_abort.trace b/src/test/modules/libpq_pipeline/traces/pipeline_abort.trace
index 254e4859975..3fce548b995 100644
--- a/src/test/modules/libpq_pipeline/traces/pipeline_abort.trace
+++ b/src/test/modules/libpq_pipeline/traces/pipeline_abort.trace
@@ -38,6 +38,7 @@ F	26	Parse	 "" "SELECT 1; SELECT 2" 0
 F	12	Bind	 "" "" 0 0 0
 F	6	Describe	 P ""
 F	9	Execute	 "" 0
+F	6	Close	 P ""
 F	4	Sync
 B	NN	ErrorResponse	 S "ERROR" V "ERROR" C "42601" M "cannot insert multiple commands into a prepared statement" F "SSSS" L "SSSS" R "SSSS" \x00
 B	5	ReadyForQuery	 I
@@ -45,6 +46,7 @@ F	54	Parse	 "" "SELECT 1.0/g FROM generate_series(3, -1, -1) g" 0
 F	12	Bind	 "" "" 0 0 0
 F	6	Describe	 P ""
 F	9	Execute	 "" 0
+F	6	Close	 P ""
 F	4	Sync
 B	4	ParseComplete
 B	4	BindComplete